A federal judge here yesterday approved the Department of Energy's new regulations that are allowing oil companies to increase gasoline prices by nearly 2 cents a gallon over the next few weeks.

U.S. District Court Judge aubrey E. Robinson Jr. approved the so-called "tilt" regulations that are aimed at increasing the supplies of unleaded gasoline by allowing oil companies to pass through more of their refining costs onto gasoline.

The regulations went into effect March 1 and are especially expected to boost the price of unleaded gas. Consumer activist Ralph Nader and the Center for Auto Safety sued the Energy Department in an effort to block implementation of the regulations on ground that as the price differential between leaded and unleaded gas increases, more motorists with cars calling for unleaded gas will switch back to leaded gas.

As a result, Nader and the center said, air quality would be diminished because the use of leaded gas in cars requiring unleaded fuel ruins catalytic converters designed to control polluting exhaust emissions.

Robinson said other court rulings do not permit him "to substitute [his] judgement for that of the agency as to the environmental consequences of the proposed actions." He added that Nader and auto safety center "have not established a lack of good faith on the part of the Department of Energy."